The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
An unmanned aerial vehicle (UAV) is a heavier-than-air flying machine that does not carry a human operator. UAV's are utilized for many different military and civilian applications such as reconnaissance, surveillance, area mapping, and/or photography, for example.
Traditionally, the use and implementation of hobby grade vertical takeoff and landing UAV's was severely limited by the relatively low lifting capacity of the same. However, recent advancements have seen the introduction of small size UAV engines which can carry payloads exceeding 30-50 pounds each, and for prolonged periods of time. As such, UAV's are now being contemplated for use in new industries, and for performing tasks never before possible. Several examples include equipping a heavy-lift UAV with an agricultural spraying module, LIDAR remote sensing equipment, or a payload basket for transporting goods from one location to another.
Although such applications are promising, the current design and construction of UAV frames is not conducive for heavy-lift applications. This is because traditional UAV frames are constructed from an elongated, generally rectangular main body onto which the payload is secured. A plurality of elongated fixed booms having an engine along the distal ends are secured onto each corner of the main body and extend diagonally outward therefrom. The length of the elongated booms depends on the lifting capacity of the UAV, but typical designs call for a boom length that is approximately twice as long as the length of the main body itself.
Unfortunately, when such UAV frames are paired with heavy payloads, i.e., payloads that require engine thrust levels at or above 40%, these long booms have a tendency to vibrate during flight. These vibrations often increase over time, and can affect the ability for the device to be stable in flight. Moreover, these vibrations combined with the non-symmetrical shape of the main body make it difficult to secure payload at the center of mass of the device. Such weight management issues therefore result in less than optimal flight characteristics, and have been the cause of several crashes. Finally, owing to the large fixed shape of such vehicles, it is exceedingly difficult to store and/or transport the same without utilizing specialized equipment or facilities. In many instances, users are forced to disassemble the vehicles for storage and transport.
Accordingly, it would be beneficial to provide a heavy lift UAV frame which can be mated with any type of avionics and/or payload package, and that does not suffer from the drawbacks described above.